Blowtorch



June 30, 1936.

' p. A. LENK BLOWTORCH Filed Dec. 21, 1953 OSMJMZMM Patented June 30, 1936 UNITED STATES BLOWTORCH David Allen Lenk, Newton, Mass, assignor to Samuel C. Brody, Brookline, Mass.

Application December 21, 1933, Serial No. 703,430

13 Claims.

This invention relates to blow torches.

Considerable difficulty is experienced in keeping blow torches continuously operating, both those having a Bunsen burner and those requiring a constant priming flame. This difficulty is due to a charring of the wick in thepressure generating tube, as a result of the excessive heat at the outside end with the result that the torch will not burn properly or is extinguished. To overcome this the end of the wick has been set back from the outside end of the pressure generating tube; but oftentimes handling of the torch causes the wick to move from the position it was placed in. One object of my invention has been to provide a means which would hold the wick in a predetermined position in the pressure generating tube and which will positively prevent it from moving to the outside end of said tube where it would soon be charred.

When the torch is turned upside down a rush of liquid into'the pressure generating tube will extinguish the torch, and several expedients such as plugs in the reservoir have been used to prevent this; but the plug does not compress the wick, and being a light object it does not stay in a desired position. To remedy this I do away with the plug entirely and tie a knot in the wick at the entrance to the pressure generating tube which is large enough to prevent any rush of fuel into said tube; but always permitting the gradual passage of fuel by capillary attraction.

The foregoing and other objects which will appear as the nature of the invention is better understood, may be accomplished by a construction, combination and arrangement of parts such as i disclosed by the drawing. The nature of the invention is such as to render it susceptible to various changes and modifications, and, therefore, I am not to be limited to the construction disclosed by the drawing; but am entitled to all such changes therefrom as fall within the scope of my claims.

In the drawing:

Figure 1 is a side elevation of my blow torch.

Figure 2 is a longitudinal section of my blow torch to illustrate the interior of the fuel reservoir and pressure generating tube.

Figure 3 is an enlarged longitudinal section broken away to more fully illustrate the position of the conical spring and wicking in the pressure generating tube.

My invention is applicable to all types of blow torches, and I have illustrated one with a fuel reservoir l2 to hold a vapor forming fuel such as denatured or grain alcohol or gasoline, having a handle l3 and a removable top section 14-, to which is united a pressure generating tube l5, oftentimes called a gooseneck tube, which extends part way down into the reservoir I2, as illustrated in Figure 2 of the drawing. Said reservoir may be made as a unit, and filled at the bottom. A combustion burner tube I6 is shown, commonly called a Bunsen burner, which has a nut-like portion at its inner end that screws onto said pressure generating tube I 5, to connect the two. The usual air control nut or ring I8 is screw threadedly mounted on said combustion burner tube 15. This invention is equally adaptable to torches which require continuous priming and do not have a Bunsen burner.

A hollow metal jet plug I9, which is closed at one end, is screwed into the outside end of the pressure generating tube l5, which plug has a jet orifice 20 drilled in said closed end, of a diameter of .013 or thereabouts.

Within said fuel reservoir l 2 is wicking 22 which extends from the bottom thereof up into the pressure generating tube l5; but not to the outer end thereof, as it is intended that a definite space shall be left in said pressure generating tube l5 5 between its outer end and the end of said wicking 22. Said wicking is tied in a knot 23 at the entrance to the pressure generating tube IE to thereby compress it and retard the flow of fuel.

This knot will not prevent fuel working its way through it gradually, but will prevent a rush of fuel into said tube l5 when it is upside down, which would extinguish the torch.

In order to definitely hold said wicking 23 spaced away from the outside end of said pressure generating tube [5, and thereby avoid charring of the wicking, I insert a member which is shown in the form of a conical spring 24, which is made of some suitable metal such as copper, bronze, et ceterabut may be made of a combination of metal and other material. This spring 24 tapers in diameter towards the outside end, which smaller outside end fits into the hollow portion of said jet plug l9. Inasmuch as the inside diameter of part of said spring 24 is less than the thickness of said wicking 22, as best illustrated in Figure 3 of the drawing, the wicking cannot possibly move to the end of the pressure generating tube where it would get charred. This also eliminates any possibility of plugging of said orifice 20.

Said wicking 22 enters the large end of said spring 24 and extends therein as far as it will go where it is held, so that said wicking remains at a predetermined point in the pressure generpossible and hence of producing a much stronger and intense blast flame. It also enables the wick to be positioned within the wick tube with its outer end spaced a substantial distance away from I the outer end of the wick tube so that flame from the priming pan, or other flame source, cannot char the wick and cause the torch to become inoperative.

The space within which the positioning momber is located is, of course, devoid of wick, and may therefore serve as a. gas expansion space. The presence of the positioning member, when made of heat conducting material, within said space creates the maximum heating effect on the already-volatilized gases within said space, thereby producing maximum gas pressure.- This space, when so filled with gas, also excludes the entrance of air, thus furthering the emission. of

- a steady stream of clear, volatilized gases.

The wick itself, when co-acting with the positioning member, may be used to adjustably expand the positioning member eitherlongitudinal- 1y or transversely along or against the inner face of the wick tube wall.

While I have shown the wick tube as of ,conventional gooseneck shape, it will be under stood that my invention is not limited to this or any other shape of wick tube. It will also be understood that the wick positioning member if desired may be made longer or shorter than is illustrated in the drawing and may or may not extend into the jet'plug. 1

What I claim is: I

1. In a blow torch, in combination, a fuel reservoir, a pressure generating tube communicating therewith, a. wick in said reservoir and tube, and a resilient member in said tube to keep said wick spaced away from the outside end of said tube.

2. In a blow torch, in combination, afuel reservoir, a pressure generating tube communicating therewith, a wick in said reservoir and extending part way into said tube, and a spring in said tube to keep said wick spaced away from the outside end. of said tube.

3. In a blow torch, in combination, a fuel reservoir, a pressure generating tube communicating therewith, a wick in said reservoir and extending part way into said tube, and a conical spring in. said tube extending in front of said wick to keep: said wick spaced away from the outside end of said tube, said spring tapering in diameter towards said outside end.

4. In a blow torch, in combination, a fuel reservoir, a pressure generating tube communicating therewith, a wick in said reservoir and tube, a jet plug in the outside end of said tube, and a conical spring in said tube to keep said wick spaced away from the outside end of said tube, said spring tapering in diameter towards said outside end, the small end of said spring entering said plug, said wick entering the large end of said spring and extending therein part of the length of said spring, the inside diameter of a extending at its large end into said tube, said wick entering and extending into said large end of said member.

6; In a blow torch, a fuel reservoir, a pressure generating tube communicating therewith, a wick in said reservoir and tube, and means frictionally engaging both the inner face of said tube and the wick for positioning said wick in pre-determined spaced relation to the outside end of said tube.- v

7 7. In a blowtorch, a fuel reservoir, a pressure generating tube communicating therewith, a wick'in said reservoir and tube, a jet plug in the outside end of said tube, there being a space between the outer end of the wick and the jet plug, and a member-located in said space and extending into said plugat one end and at its other end frictionallyengaging both'the inner face of said tube and the wick forpositioning said wick in pre-determined spaced .relationto said jet plug.

8. In a blow torch, a fuel reservoir, a pressure generating tube communicating therewith, a wick in said reservoir and tube, a jet plug in the'outside endof said tube, there being a space between G the outer end of the wick-and the jet plug, and a member located in said space and extending into said plug at one end, the wick extending part way into the other end of said member and being frictionally retained thereby, and said member having a portion frictionally engaging the inner face of said tube for positioning said wick in pre-determined spaced relation to said jet 9. In a blow torch,a fuel reservoir, a pressure generating tube communicating therewith, a wick in said reservoir and tube-and terminating a distance from the outer end of said tube, and an expansible positioningmember frictionally engaged against the wall of the wick tube for adjustably supporting the outer end of the wick in desired position within the tube, said wick being frictionally locked with the inner end of said positioning member. I V a 10. In a blow torch, a fuel reservoir, a pressure generating tube communicating therewith, a wick in said reservoir and tube and terminating a distance from the outer end of said tube, and an expansible positioning member frictionally engaged against thewall of the wick tube for adjustably supporting the outer end of the wick in desired position within the tube, the outer end of the wick be-ing engageablewith the inner end of the positioningv member.

ing a jet opening adjacentits outer end and a wick in said tube, there beinga space between the outer end of the wick and the jet opening,

and a wick positioning device frictionally lodged '75 within said space and constrictively engaging the a. wick positioning device within said space, said wick adjacent the outer end thereof. device being re-active at one end against the 13. A blow torch, comprising a. wick tube havouter end of the wick and being re-active at its ing a. closed outer end provided with a jet orifice, other end against the outer end of the wick 5 a. wick in said tube, there. being a. space between tube.

the outer end of the wick and the jet orifice, and DAVID ALLEN LENK. 

